Are Birds Reptiles? Uncovering Nature’s Relations

Are Birds Reptiles

There are thousands of animal species on the planet, and some have a significant resemblance to each other. 

Two species that are often confused are birds and reptiles since they have some misleading similarities.

We need to know all there is to know about reptiles and birds, so we can differentiate them. 

What are the similarities between the two, and what are the differences between them? Most importantly, let’s answer the question;

Are Birds Reptiles?

Birds are reptiles. Birds and reptiles are both in Kingdom Animalia, and they share a common evolutionary line. They are both descended from dinosaurs, but evolution sets them apart; however, birds are considered reptiles. 

Birds may look different, but they are closely related to reptiles. Some structures in birds are common to those in reptiles, and they serve almost similar purposes suggesting a common ancestry.

Understanding How Birds Are Reptiles

Reptiles include animals like lizards, turtles, snakes, and birds.  Birds are reptiles, but frogs and toads are not. 

So what is a reptile? What are the distinguishing features that make them related to birds and not mammals?

1. Reptiles are cold-blooded

 This is a misleading statement since they don’t have cold blood; what it means is that they are primarily exothermic. 

A human body will maintain its temperature at about 98.60 F, but reptiles can bask at places and raise their blood temperature to about 1200F. So the blood is, in fact, warm only that the heat is drawn from the surrounding. 

Birds are endothermic, but it is not necessarily a difference between them. Some reptiles are capable of producing heat at certain times of the year.

Only mammals and birds are endothermic, and some reptiles like pythons can produce heat while incubating their eggs.

2. Reptiles lay eggs

This is another characteristic that links reptiles to birds. All birds lay eggs the same as most reptiles. 

Many reptiles, for instance, a Boa constrictor, don’t lay eggs; they give birth to live snakes.

About 30% of all snakes and 15% of lizards give birth. But the shared laying of eggs between birds and most reptiles shows that they are more closely related to each other than mammals.

3. The Presence of scales on the bodies

 Most reptiles are covered with scales for protection and heat conservation. 

This is a fact that is also seen in birds that have scales on their feet which provides protection.

Feathers are the defining characteristics of birds, and feathers are modified scales. This shows that birds and reptiles once shared an origin, but they were forced to adapt differently to their environments. 

4. They have a diapsid skull

A diapsid skull is a skull that has two holes behind the eyes on each side for muscles to pass through. 

The ancestors of all modern-day reptiles had diapsid skulls, but reptiles can lose these holes during evolution. 

For instance, lizards have gotten rid of the bottom of one of the holes, making it open. In birds, the hole has been restructured to the point that there are no clear holes. 

This is also seen in some reptiles; thus, it strengthens the relationship between reptiles and birds.

5. They share a more recent ancestor

Birds and all other reptiles share a more common ancestry than any other animal group on earth.  This is the factor that genuinely unifies them as a group.

It is for this reason that birds have to be included as reptiles. They are the only living descendants of the dinosaurs. Crocodilians are more closely related to dinosaurs than any other animal; thus, birds are reptiles.

Characteristics Of Reptiles

Reptiles have adapted over the years, and they currently live in all kinds of environments except those that are very cold.

From lizards, snakes, crocodiles, and many others, there is a high chance that you will meet a reptile every day even if you don’t know it. So let us get to know them better;

1. They are vertebrates

This means that they have a backbone and spinal cord. Snakes have a very flexible spine, and that is why it seems like they have no bones. The vertebrae protect the spinal cord, and it goes all the way from head to tail.

2. They are cold-blooded

This means that they have no mechanism of moderating their internal temperature; thus, it varies depending on the environment. 

When it is cold, they move to warmer areas to warm up, and they move away from the heat when it is hot. Some reptiles can produce their body heat during certain times of the year. This is common in cold seasons or during the breeding season.

3. Most have scales on their bodies

Snakes, birds, and crocodilians all have scales on their bodies to help keep them safe. 

The scale is armor against predators, and it helps keep the body temperature constant. Some reptiles, however, have shed off their scales over time, and they have smooth bodies. 

4. They have dry and water-tight skin

This is a characteristic that differentiates reptiles from amphibians. Reptiles have no secretory glands on their skin; thus, they produce no slime. Some scales are very smooth, which makes them feel slimy, but they are not.

5. Most reptiles lay eggs

Most lay eggs like birds and bury their eggs in the ground for incubation like crocodiles. 

Others like pythons incubate the eggs using their body heat since they are partly endothermic. 

Some reptiles give birth to live young like mammals. Their eggs are not hard-shelled like birds’; reptile eggs are leathery and soft. All layers do it on dry land, even if they spent most of their lives in the water.

What Are The Differences Between Birds And Reptiles?

We have established that birds are reptiles, but there are still some notable differences between them. It is important to note all the differences to have a clear distinction between the two;

1. Reproduction

Both birds and reptiles lay eggs; the difference comes in when we take a closer look. All birds lay eggs, but not all reptiles lay eggs; some give birth to live young thus have internal fertilization.

Another difference in reproduction is how the eggs are incubated. Birds sit on their eggs to keep them warm and for the young to grow inside until the incubation period is over. 

On the other hand, reptiles lay their eggs on dry land and bury them since they cannot generate heat to warm the eggs. Some species of pythons incubate the eggs by generating body heat, but it is rare in reptiles.

2. The number of limbs

All birds have two legs since they mostly fly. The legs are adapted for the bird’s environment, and those that fly have weak legs that can’t be used for long walks. Reptiles, on the other hand, have either four legs or none.

Reptiles that live in or around water bodies have webbed feet and appropriately adapted tails to help them swim faster. 

Those that live on land have legs that allow them to run and climb like lizards. Snakes have no legs; thus, they crawl and swim.

3. Presence of wings

All birds have adapted, and their forelimbs have developed into wings. Most birds use these wings to fly, but not all can fly; even if they are not used, they are present.

Reptiles, on the other hand, do not have wings. Some reptiles can fly, such as the flying lizard, which has a membrane between its front and back legs that helps it stay in the air. These are, however, not wings.

4. Types of scales

Both reptiles and birds have hard scales on their bodies. The difference is that scales completely cover reptiles while birds only have scales on their legs. Feathers are scales, but they are modified to be softer and lighter to facilitate flight.

5. Body temperature control mechanisms

Reptiles draw heat from the environment. When they need to get warm, they bask in the sun to raise their body temperature. When they need to cool down, they go into a shed or some water.

Birds, on the other hand, use internal mechanisms to control their body temperature. They reduce heat loss by building up fat reserves and using the feathers to trap air molecules. They can also constrict blood flow to minimize heat loss.


Birds are reptiles, a lot of traditional knowledge goes against this, but they are very closely related. 

They have similarities in ancestry, metabolism, body structure, and feeding habits. Years of evolution have split these two groups, but a keen eye could see that they are one.

Reptiles and birds do not resemble each other at first glance, so they seem distant, and it is hard to imagine that they are related.

They have some differences in reproduction and physical appearance, but even members of a family look different. 

Amphibians like toads and frogs might look like reptiles, but they have wet scales; they produce slime, which distances them from reptiles.